Signaling generator mechanism



y 13, R. K. HELLMANN 2,420,638

S IGNALING GENERATOR MECHANISM Filed April.l5, 1944 4 Sheets-Sheet l @91 ium 13% as Illlllli IIIIH INVENTOR.

Pan/10rd Id Hal/mam? BY M1, M v Ax HTTO/FNEYS y 13, 1947. R. K. HELLMAWv 2,420,638

SIGNALING GENERATOR MECHANISM Filed April 15, 1944 4 Sheets-Sheet 2 INVENTOR. Pemha/d K. Hellman HTTUIPNEYS May 13, 1947. R. K. HELLMANN' 2,420,638

SIGNALING GENERATOR MECHANISM Filed April 15, 1944 4 Sheets-Sheet 3 F" 7 I 9 7": g

8 J0 1? I w b a? I N VEN TOR.

HTTOIPNEYS y 1947* R. K. HELLMANN 2,420,638

SIGNALING GENERATOR MECHANISM Filed April 15, 1944 4- Sheets-Sheet 4 A K I H I femhard Hellman/1 M,-/Gw1/ v in Patented May 13, 1947 UNITED STATES PATENT OFFICE SIGNALING GENERATOR MEGHAN ISM Reinhard K. Hellmann, Meriden, Conn-., assignor to Great American Industries, Inc Meriden, Conn, acorporation of Delaware ApplicationApril 15, 1.94 Serial No; 531,225

2 Claims. 1

This invention relates to a structurally and functionally improved generator mechanism and in itsmore specific aspects aims to provide a unit of this character combined with a telephone in strument or assembly in a manner such that it will be unnecessary to include in the latter a separate ringing or corresponding signaling mechanism.

It is a primary object of the invention to provide a unit of this type and which will be ofsimpie and compact design such that it may readily be combinedwith a telephone instrument. Moreover, a unit constructed in accordance with the teachings of this invention will'be extremely light in weight and include. relatively few parts, each individually simple and rugged in construction; the entire assembly being capable of economic manufacture and operating. over long periods oi time with freedom from all difficulties.

A further object of the invention is that of providing in a telephone mechanism a generator embodying the aforementioned advantages and with which there may be associated an improved switching or disconnecting mechanism suchthat portions of the telephone mechanism will be automatically or otherwise disconnected from the circuit when the generator is operated;

Still another object is that of furnishing a generator of this type which, while capable of being readily combined with a telephone or similar assembly, may in manyrespects be regarded as an independent unit. As such, it will be susceptible to ready replacement when desirable, without the necessity of disturbing either the transmitter or receiver of the instrument.

An'additional object is that of providing an assembly of this nature and which will be substantially waterproof inaddition to guarding against the entrance of other foreign elements into its mechanism.

With these and other objects in mind; reference is had tot'he attached sheets of drawings illustrating practical embodiments of the invention, and in which:

Fig. l is a diagrammatic representation ofa portion of a telephone circuit and showing the generator included therein.

Fig. 2 is a sectional side View of a telephone instrument combinedwith a generator;

Fig. 3 is an enlarged and fragmentary sectional view of the receiver end portion of the teleplione instrument as shown in Fig, 2;

Fig. 4 is a'tran'sverse sectional View taken along the lines 4"--4' andin the-direction of the arrows as indicated in Fig. 3;

Fig. 5 is a View similar to Fig. 3 but showing certain of the parts in elevation;

Fig. 6 is a sectional viewta'ken along the lines ii-G and in the direction of the arrows as indicated in Fig; 2;

Fig. 7 is a view similar to Fig. 3 but showing alternative form of mechanism;

Figs. 8, 9* and 10 are transverse sectional views taken respectively along the lines 8-8, 9 and ti -46 and in the direction of the arrows as indicated in Fig. 7;

Fig. 11 is aview similar toF'l'g. 3 but showing an alternative construction;

lg. 12" is a sectional view taken along the lines l2--l-2 and in the direction of the arrows, as shown in Fig. 11;

Fig. 13 is a sectional side view taken through a further stator-rotor assembly;

Fig. 14 isa plan-.viewthereoi;

Fig. 15 is a side elevation of the core member; and

Fig. l6-is a perspective view of an alternative form of constructionwhich is shown or embodied in a rotor.

The present invention is primarily intended for use in connection with telephone instruments and especially instruments of the hand-set type which do not employ an extraneous current source, for example, in the form of batteries. As shown especially in Fig. 2, the assembly may embrace a hand-set including a more or less conventional handle portion 23 having at its opposite ends 2| and 22 cavities which receive sound-powered receiver and transmitting units 23 and 25 of any suitable design. The outer ends of the cavities may be'defined' by ear and mouth pieces 25 and "530i conventional or other design.

At this time it will'be observed that the cavity defined by the end'portion- 2| is of sufiicient area to accommodate at its inner end a generator unit indicated by the reference numeral 21. As shown in diagrammatic manner in Fig. l, the transmit ter and receiver units Ztiand 23' are connected toeach other and to' one of a pair of leads 28; The generator 27 is also connected tothis lead. A switch diagrammatically indicated at 'ifi'serves to optionally connect the transmitter and receiver assembly to the second of the leads 23 or else connect the generator 21 to that lead.

Now referring to the detailed construction of one preferred form of generator, attention is invited to Figs. 2 to 5 inclusive. As will be seen in these-views; reference numeral 35 indicates a stator which, as illustrated, may be of cupshaped configuration and formed of magnetic material of high permeability such as iron or one of the well-known high permeability alloys. This stator is supported upon a base plate 32 by means of legs or extensions 3!. The plate 32 is preferably formed of a non-magnetic material and bears against a flange portion 33 formed in the receiver cavity. A bracket or strap 34 may extend between the plate and the receiver 23 so as to maintain a proper spacing between the generator and receiver units, and to also prevent movement of the same within the cavity when the ear piece 25 is in position.

The rim of the stator is defined by an annular series of teeth 35. These teeth are preferably formed by providing slots in the rim of the stator body; the width of these slots being substantially equal to Or wider than the width of the teeth. Disposed within the stator body and fixed against movement with respect to the same is a permanent magnet This magnet is conveniently ring-shaped and magnetized along the axis of rotation. Interposed between the magnet and the rim of the stator is a coil 31. This coil is preferably formed of copper wire and its impedance can be matched to that of the line circuit by incorporating in the coil a proper number of turns formed or a wire of a given size.

In order to provide a compact structure, a rotor 38 is employed which may be of disc form and of a diameter such that it may be disposed within the space defined by the stator. Teeth 33 extend radially from this rotor and provide an annular series corresponding in number, general dimensions and spacin s to the teeth 35 of the stator. Likewise, the rotor is preferably formed of a material similar to that from which the stator is formed. The rotor is supported upon a shaft 43 which is rotatably journaled in a bearing mounted by the stator assembly and has its opposite end rotatably supported by the plate 32. This shaft is preferably formed of a non-magnetic material and has secured to it the final element of a drive assembly. Such element takes the form of a gear 4| and the drive may include a suitable number of gear units 42, the teeth of which successively mesh with each other and finally with the teeth of the gear 4!. These gear units or assemblies are rotatably and suitably supported by the base plate 32.

The outer end of the gear train or drive is defined by a gear 43 which, as especially shown in Fig. 6, has on its outer face a circular series of teeth 44 defining an annular ratchet. A springpressed pawl traverses the teeth 44 and is carried by a plate or support 45 secured to a shaft 4'1. This shaft extends through the wall defining the end of the receiver cavity and is rotatably journaled therein. Beyond such wall, the shaft 47 mounts a handle 48 which may include any desirable configuration convenient for engagement and shifting by the finger or hand of the operator.

As illustrated especially in Fig. 6, the plate 45 preferably includes an arm and an arcuate section. The arm conveniently has as an integral part the resilient portion 53 which mounts the pawl 45. A spring 43 serves to return the shaft 4'! to a predetermined position from which it may be moved by the handle or actuator 48. Rotation of the shaft 4'! beyond predetermined points is prevented by, for example, the arcuate portion of the plate 45 engaging the inner edge of the cavity within which it is disposed. Accordingly, the handle or actuator 43 may not be moved beyond predetermined points.

When so moved in one direction, and by means of the thumb or hand of the operator, it is apparent that the pawl 45 will engage one of the teeth 44 and move the gear 43 in accordance with the movement of the handle 48. Upon the latters being released, the shaft 41 will return to its normal position under the influence of the spring 49. In such return, the pawl 45 will be free to override the teeth 44. Thus, the gear 43 may continue to rotate so that no interruption to continued driving of the rotor 38 will occur during such return movement of the handle or actuator.

Now with a view to providing a structure of improved design and by means of which the switch 29 as diagrammatically indicated in Fig. 1 will be opened from the telephone-line position and closed through the generator-line branch, it will be noted, as shown in Figs. 3, 4 and 5, that a switch including spring arms 5|, 52 and 53 is disposed preferably beyond the plate 32. Each of these spring arms carries contacts. The arm 52 is biased towards the arm 53 and may be connected to the lead 28. The arm 5| is conveniently connected to the generator assembly and the arm 53 is connected to that lead which extends to the transmitter-receiver grouping. An actuating portion 54 conveniently of di-electric material is secured to plate 46 and more particularly the arcuate portion thereof. An extension 55 which cooperates with the actuator 54 is conveniently secured to the spring arm 52. The contact of arm 52 being normally engaged with the contact of arm 53 it follows that the voice circuit is normally closed. However, simultaneously with a shifting of the handle or actuator 48 occurring, the portion 54 will act as a wedge in cooperation with the portion 55 to swing the arm 52 away from the arm 53. Consequently, the circuit between arms 52 and 53 will be interrupted but the circuit between arms 51 and 52 will be closed to connect the generator into the line. Thus, a switch structure is furnished which automatically connects the generator into the circuit and disconnects the transmitter and receiver assembly therefrom when an operator actuates the calling generator.

It is obvious that any suitable packing or equivalent structure may be provided between the casing portions and the shaft 41 to prevent the entrance of foreign material or moisture into the switch or generator mechanisms. Likewise, the ear piece of the set mayin accordance with conventional practice-have its opening covered. Also, a gasket may be provided at this point. Therefore, foreign material and moisture may not enter through the outer end of the cavity. Consequently, a unit may be furnished which will be substantially immersion-proof. Likewise, as will be understood, the bracket or extension 34 may actually provide a terminal block (not shown) and to which the several necessary leads may be coupled in order that the parts may be suitably connected into the transmitting line.

In general operation, it has heretofore been seen that as the handle is actuated and aside from the operation of the switch mechanism, the gear train will be operated to cause a rotation of the sprocket 4i. Conveniently, a 20-to-l step-up ratio may be provided and the handle 48 may be capable of oscillation through anywhere from 20 to As the rotor revolves and the relative positions of the stator and rotor teeth change, the flux driven by the permanent magnet through the stator and rotor assembly and the air gap is changed rapidly and thereby sets up an alternatin'gele'ctromotive force in the coil. This force will betransmitted through leads 23. Ha second telephone" assembly is connected to these, the transmitter and/r receiver units incorporated in: that s'econdset will be vibrated at acoustical frequencies. This will produce a signal such that the attention of the operator will be directed to the fact that an incoming call is being received. As will be appreciated, if more than one projectionof the handle 48 is necessary, the return movement of the handle will not prevent continue'd rotation ofthe gear train driving the rotor. Due to-the fact that the switch'mechanism automatically connects in the transmitter and receiver assembly with the circuit asthe spring l9 mo'v'esthe shaft 41- to its initial or normal position, the operator will immediately be cognizant of the fact that the person called is answering throng-nine second" telephone connected to the masses;-

I n the formofoonstruction shown in Figs. 7 to Lu a-receiver portion has been illustrated and which is provided-With a bore such that the receiver unit may be introduced at one end and the generator assembly or unit at the opposite end" thereof. More particularly, the end portion 56-;is' formed with abore 51 and the receiver unit 23' is disposed Within the bore and retained in position. in any suitablemanner. A base plate 5811s threaded into the opposite end of the bore and against the adjacent end edge of the end portion; This plate 53 r'otatably supports actuating. member 59 upon a boss A gear 6! may: be carried by the plate and within a re cessedlportion of plate 53. The teeth of gear Ell mesh with the teeth of a pinion 62. The latter is mounted upon a shaft cs conveniently supported in a bushing 64. This bushing is supported in a bracket 65 and to that end extends through an arcuate slot formed in the base plate 53. Through similar slots, retaining bolts eii may extend in engagement with the frame The latter may have rotatable bearing with a boss portion 61.

Thus, the frame will be capable of oscillation around the boss 6'! or any equivalent mounting portion. Preferably, this oscillation should be limited to only a very few degrees. such limitation will be effected by the bolts 66 and the bushing 64' contacting the ends of the slots through which they pass. Also, the frame will normally return to a predetermined position. This result may be achieved in any desirable manner as, for example, by employing a spring 53 which encircles the boss 6!] and bears against the end of the bushing 6'4.

In any event, it will be understood that as the plate 59 or its equivalent is rotated with respect to' the plate 58, the shaft 63 is driven. Simultaneously, and immediately upon initiation of such drive, the frame 65 will be shifted with respect to'the plate 8j This will cause an operation of a switch assembly as hereinafter described.

The generator in this embodiment may include a st'ator 69 mounted by the bracket 65. A rotatably supported shaft Ill mounts the rotor H. Boththe stator and rotor may be cup-shaped and formed with teeth or slots in the manner afore described in connection with the structures of Figs, 1 to 5. If desired, the stator and rotor may be overlapped or partially telescoped with respect to each other. A gear train 12 serves to connect the shaft 16 with the shaft 63.

As especially shown in Fig, 10,-aportion-of the frame 65 may lieadjacent an extension 131 of a contact-mounting switch element 14'. Disposed to each side ofthis element are further contactcarrying elements 15 and l6. Thisswit'ch assembly is mounted by the plate 53 or any other rela tively fixed portion. It corresponds in function to the switch assembly heretoforedescribed and identified by the numerals El, 52 and 53. Thus, returning to Fig. 1, we may regard the switch element '54 as corresponding to the switch 29'. This element will normally be biased to have its contact in electrical engagement with one of the adjacent contacts carried by the-elements 15 or- To; Such elements will be connected one to each of leads 23; However, upon the plate 59' being rotated, it is apparent that, due to the movement ofwhich the bracket. s5 is capable with respect to that plate, the extension 73 will be engaged by the bracket to disconnect the telephone transmitter and receiver from the transmitting line and to connect a lead'extending' from thegenerator assembly to such line. Consequently, simultaneously upon the operatorsaotuating the parts to provide for a signal, the generator will be properly connected into the circuit. Such con-. reaction will be. continued until the spring 68 or its equivalent has returned the parts to their normal or initial position.

If it is desired to maintain the connection between the telephone leads 23 and the generator for a longer period, a ratchet drive similar to that heretofore described'in connection with the reference numerals 44' and 45 may be employed. Such a drive has been generally illustrated in Figs. 11 and 12. For identification purposes, the parts corresponding to those heretofore described in connection with the earlier figures, have had the same reference numerals with the addition of a prime mark applied to them.

As illustrated especially in Fig. 8, the body of the stator 69 may be reduced so that only two sectors, each of approximately remain, In that case, coils Tl may encircle the magnet. These coils may be connected to each other either in series, or in parallel as desired and it is obvious that the rotor need not necessarily be cup-shaped but, similar to the construction in Figs. 1 to 5 inclusive, may be, for example, in the form of a fiat disc. Likewise, the magnet may be associated either with the rotor or the stator as desired.

As will be understood, by thus reducing the stator and consequently the number of teeth or slots which form a part of the same, it is feasible to generate low frequencies. In the latter connection, both the stator and rotor may be reduced to similar configurations which will each include two sectors of 90. Thus, the generator will not produce frequencies in the voice range and may, for example, produce frequencies between 15 and 20 cycles. Moreover, if each of the sectors have their teeth provided with smaller spacings, the generator will produce a low frequency and therefore can be used for both sound calling as well as low frequency calling.

As will be appreciated in connection with all of the constructions herein described, a substantially sealed unit will be provided and so that foreign material may not enter into the same. More especially as illustrated in Figs. 2 to 6, the diaphragm of the receiver unit 23, together with the gaskets and gear piece adjacent thereto will prevent moisture or other objectionable substances from enteringthe cavity within which this receiver, as well as the generator, is disposed. The

fit of the shaft 41 in its bushing may be suificiently close to prevent the entrance of moisture and foreign material through the base end of the receiver cavity. In the form of construction shown in Figs. 7 to 10, the receiver and associated parts will again prevent the entrance of moisture and foreign material through the base end of the receiver cavity. In the form of construction shown in Figs. 7 to 10, the receiver and associated parts will again prevent the entrance of moisture through one end of the bore 51 while the plate 53 will prevent the entrance through the opposite end of the bore. In the latter connection, it will be understood that the very limited degree of movement of which the bracket 65 is capable with respect to the plate 33, will not require any pronounced enlargement of the slots through which the bolt 66 and bushing 64 pass. Accordingly, the entrance of foreign particles through these slots is substantially prevented.

If it is not desired to employ an automatically actuated switch mechanism for connecting the transmitter and receiver of the telephone and the generator into and out of the line leads 28, a structure such as that illustrated in Figs. 11 and 12, may be employed. As will be seen in these views, an actuating mechanism is utilized which corresponds substantially to that illustrated in connection with Figs. 7 to 10. This is excepting only that the bracket portion will not have shifting movements with respect to the mounting plate. Instead, a switch assembly [8 is utilized and which will have the functional characteristics (insofar as connect and disconnect operations are concerned) as the switch assemblies to 53 and i5. This switch 18 may be actuated by a push button 19 or its equivalent. The latter is enclosed in, for example, a rubber cover 80 which is vulcanized or otherwise sealed in contact with the frame or surface of the unit. Thus, moisture and foreign materials may not enter through the opening through which the actuator connected to the head 19 extends. For the sake of simplicity of illustration, the push button 19 and associated structure has been shown as extending through the upper wall of the instrument casing. As will be understood, it might extend in any desired or convenient direction.

Obviously, in this form of construction, it will only be necessary to actuate the switch 78 by pressing upon the cover 85 to accordingly transmit thrust to the actuator 19. With the parts in this position, the transmitter-receiver unit will be disconnected from the second lead 23 and the generator will be connected thereto. Accordingly, if the generator-operating mechanism is now actuated, suitable current impulses will be transmitted through the leads 28 to cause further instruments connected thereto to be operated in a manner such that a proper signal is produced. Thereupon, the operator may release pressure upon the actuator 79 so that the parts of the switch assembly 18 may be restored to their initial positions. Thereupon, the instrument connected to the leads 28 may be utilized in the usual manner.

If desired, the magnets incorporated in the generator might be modified to include a construction such as is shown in Fi s. 13 to 15. By means of such constructions the stray flux factor is reduced. As will be observed in these views, a ring-shaped magnet 92 is employed. It is magnetized radially so that the inner periphery 81 is, for example, a south pole and the outer periphcry 82 is a north pole. A coil 83 may be disposed concentrically and for the purposes as heretofore described in connection with earlier figures. An encircling member 84 is suitably secured to and encloses the magnet 92 and is provided with teeth 85 as also heretofore described in connection with the stators and rotors. In this manner, a cupshaped assembly is provided, the several components of which are, in effect, integral. A disclike member 86 may be secured to the rotatable shaft 81. This member may, similar to the disc 33, again be formed with teeth which are suitably spaced. To prevent relative rotation occurring between the magnet and the core 81, the latter may, for example, be formed with slots 88 into which portions of the former may key. Both the enclosing portion 84 as well as the disc 86 and the inner portion 8| should preferably be formed of magnetically soft material.

As illustrated in Fig. 16, any or all portions of the generator may be slotted. More particularly, as shown in this view, the rotor 89 is formed with radially extending slots 90. The material of the generator parts should be magnetically soft and have a high magnetic permeability but at the same time provide for a low eddy current loss. Materials such as silica steel are suitable for this purpose. By means of the radially extending slots, the concentric structures are interrupted. This feature may also be included "m any other of the parts of the generator. Such an arrangement will serve to further reduce the eddy current losses.

In the foregoing description, the generators have been illustrated and described as disposed within the cavities or bores which house the receiver units. This is in many respects a preferred construction. However, as will readily be understood, the generator might be housed in either of the bores of the hand-set which receive the sound-translating units. In fact, the hand-set might be constructed in a manner such that only a single cavity or recess suitable for the reception of the generator would be necessary or provided. Thus, again in this connection, the present disclosure is to be taken in an illustrative rather than in a limiting sense.

Thus, among others, the several objects of the invention as specifically aforenoted are achieved. Obviously, numerous changes in construction and rearrangements of the parts might be resorted to without departing from the spirit of the invention as defined by the claims.

I claim:

1. A generator including a rotor unit, a stator unit, a shaft connected to said rotor unit, a drive extending from said shaft, an actuator connected with said drive, a bracket supporting a part of said drive, means for movably mounting said bracket and whereby, upon a thrust being transmitted from said actuator, said bracket will be shifted, and a switch mechanism connected to said generator and actuated by the shifting of said bracket.

2. A generator including a rotor unit, a stator unit, a shaft connected to said rotor unit, a drive extending from said shaft, an actuator connected with said drive, a bracket supporting a part of said drive, means for movably mounting said bracket and whereby, upon a thrust being transmitted from said actuator, said bracket will be shifted, a spring for normally maintaining said bracket in a predetermined position when not subjected to a thrust by said actuator, a switch mechanism disposed adjacent said bracket, and said switching mechanism being actuatable by said bracket 10 upon the latter shifting against the action of said. spring. Number Name Date REINHARD K. HELLMANN. 2,262,532 Harmon Nov. 11, 1941 2,193,675 Merrill Mar. 12, 1940 REFERENCES CITED 5 2,237,823 Nowosielski Apr. 8, 1941 The following references are of record in the 21245358 G055 June 1941 file of this patent: 2,341,171 Alessandn Feb. 8, 1944 2,212,192 Howell Aug. 20, 1940 UNITED STATES PATENTS 2,146,588 Merrill Feb. 7, 1939 Number Name Date 10 2,146,603 Stephenson Feb. '7, 1939 495 139 McLeod Apr 11 1393 2,334,157 h OV. 1 1,151,530 Neuland. Aug. 24, 1915 FOREIGN AT 1,648,564 Pattay Nov. 8, 1927 1,771,870 Banzhofi" July 29, 1930 Number couptry Date 1 898 728 Hufi Feb 21 1933 15 11 ,838 Australia Sept. 25, 1941 272,472 Great Britain Apr. 26, 1928 2,056,557 Bayerdorfer Oct. 6, 1936 

